Each individual animal may use a different strategy for looking for the platform during the probe trial; consequently, we calculated the average proximity to the former location of the platform from your recording

Each individual animal may use a different strategy for looking for the platform during the probe trial; consequently, we calculated the average proximity to the former location of the platform from your recording. isoflurane. After the behavioral test, the mice were sacrificed, and the protein expression level of acetylcholinesterase (AChE), choline acetylase (ChAT) and 7 nicotinic receptor (7-nAChR) were measured in the brain. Each group consisted of 12 mice. We found that isoflurane exposure for six hours impaired the spatial memory of the mice. Compared with the control group, isoflurane exposure dramatically decreased the protein level of ChAT, but not AChE or 7-nAChR. Donepezil prevented isoflurane-induced spatial memory Fanapanel impairments and increased ChAT levels, which were downregulated by isoflurane. In conclusions, pretreatment with the AChE inhibitor donepezil prevented isoflurane-induced spatial memory impairment in aged mice. The mechanism was associated with the upregulation of ChAT, which was decreased by isoflurane. == Introduction == Nearly 1020% of elderly patients suffer from postoperative cognitive dysfunction (POCD) within 36 months after surgery[1],[2]. Although many authors[3],[4],[5]believe that POCD is usually self-limited, POCD is still a major clinical issue. Monk[6]exhibited that patients going through POCD are at an increased risk of death in the TPO first year after surgery. Steinmetz[7]showed that POCD after noncardiac surgery was associated not only with increased mortality but also with the risk of leaving the labor market prematurely and dependency on social transfer payments. However, there is currently no clinically available treatment to prevent POCD. Although some studies have not found any differences in the rates of POCD when comparing regional and general anesthesia[4],[5], exposure to general anesthesia is still considered a possible cause of POCD in the elderly[8],[9]. Many studies have shown that volatile anesthetics impair the spatial memory of aged rats[10],[11]; however, the mechanism is not well comprehended. Although volatile anesthetics have been shown to induce apoptosis in cultured cells[12],[13], there is no evidence to show the relationship between neural apoptosis and cognitive dysfunction induced by volatile anesthetic exposure in older animals. Theoretically, the anticholinergic properties of drugs are a biologically plausible cause of cognitive dysfunction in elderly subjects. Notably, the anticholinergic drug scopolamine has been shown to induce or exacerbate preexisting cognitive impairment[14]. Moreover, three cross-sectional population-based studies have exhibited that anticholinergic drug Fanapanel intake is an important factor in determining the severity of cognitive impairment[15],[16],[17]. Because previous studies have shown that volatile anesthetics have anticholinergic properties[18], we hypothesized that pretreatment with the acetylcholinesterase inhibitor donepezil, which has been approved by the Food and Drug Administration (FDA) for the treatment of Alzheimer’s disease, may prevent isoflurane-induced spatial memory impairment in aged mice. == Results == == Donepezil pretreatment prevented spatial memory impairment from isoflurane exposure == As showed inFigure 1A, the statistical analyses show that the repeat factor (days) experienced significant effects around the latency (p<0.001); the overall group factor also had a significant effect on latency (p<0.05). Post hoc Bonferroni analysis showed that animals in the isoflurane exposure group required longer to find the platform than mice in the isoflurane+donepezil group (p<0.005) and the control group (p<0.05). However, no interactive effect between group and days was found (p>0.05). == Determine 1. Donepezil pretreatment prevented spatial memory impairment induced by isoflurane exposure. == Following pretreatment with donepezil or saline, spatial memory was tested with the Morris water maze two weeks after exposure to isoflurane or the carrier gas. A: In spatial acquisition trials, the imply latency to reach the platform was longer in the isoflurane group compared with the control group (p = 0.04) and the isoflurane+donepezil group (p = 0.008). B: Swimming speed was similar among the four groups. C: In the probe trial, the Fanapanel percentage of time spent in the target quadrant was longer than the average percentage spent in other quadrants (p<0.05) for all four groups, but there were no differences between the groups for the percentage of time spent in the target quadrant. D: The average proximity to the target in the probe test of the isoflurane group was further away than the average proximity in the control group (p = 0.023). N =.